• Deep Artificial Neural Networks-taliem-ir

    Deep Artificial Neural Networks as a Tool for the Analysis of Seismic Data

    تومان

    The number of seismological studies based on artificial neural networks has been increasing. However, neural networks with one hidden layer have almost reached the limit of their capabilities. In the last few years, there has been a new boom in neuroinformatics associated with the development of third-generation networks, deep neural networks. These networks operate with data at a higher level. Unlabeled data can be used to pretrain the network, i.e., there is no need for an expert to determine in advance the phenomenon to which these data correspond. Final training requires a small amount of labeled data. Deep networks have a higher level of abstraction and produce fewer errors. The same network can be used to solve several tasks at the same time, or it is easy to retrain it from one task to another. The paper discusses the possibility of applying deep networks in seismology. We have described what deep networks are, their advantages, how they are trained, how to adapt them to the features of seismic data, and what prospects are opening up in connection with their use.

     

  • Determinants of leadership-taliem-ir

    Determinants of leadership in online social trading: A signaling theory perspective

    تومان

    Online social trading offers an opportunity for less-experienced individuals or frms to follow top traders by mimicking their behavior, but little is known about the determinants of leadership that shape such relationships. To study this, we build on signaling theory using fxed-effect panel least squares stimations to analyze 250 top traders in a network of around 1100 traders; we examine their trader credentials, volume of trades, performance, and risk signals. Contrary to our initial expectations, fndings show that trader credentials are more important than performance, volume, or risk signals, but there are signifcant differences between virtual and real money traders. This study proposes a network signaling theory approach by linking it to herd behavior and the disposition effect. Our fndings can have practical implications not only for top traders, followers, and social trading platform managers but also for policy-makers and regulators of such investment instruments.

  • Energy-aware Scheduling-taliem-ir

    Energy-aware Scheduling for Information Fusion in Wireless Sensor Network Surveillance

    تومان

    Energy-aware Scheduling for Information Fusion in Wireless Sensor Network Surveillance Kejiang Xiaoa, Rui Wangb, Hua Dengc, Lei Zhangd, Chunhua Yang*a aSchool of Information Science and Engineering, Central South University, Changsha, China bSchool of Computer and Communication Engineering, University of Science and Technology Beijing, Beijing, China cInformation and Communication Company of State Grid Hunan Electric Power Company, Changsha, China dDepartment of Computer Science, Georgia State University, Atlanta, USA Abstract Effective energy control while maintaining reliable monitoring performance becomes a key issue in wireless sensor networks (WSNs) based surveillance applications. While importance difference of surveillance zone, limited energy and dynamic network topology pose great challenges to surveillance performance. It is necessary to adjust sensor nodes awakening frequency dynamically for information fusion. Thus an energy-aware scheduling with quality guarantee method named ESQG is proposed in this paper which considers sensor nodes residual energy, different importance degrees of the surveillance zone and network topology comprehensively. It first uses a Voronoi diagram to determine the effective scope of each sensor node and then calculates node importance according to its residual energy and the importance degree of the effective scope. Then ESQG utilizes the importance of individual sensing scope and current forwarding costs to further compute node importance and awakening frequency for information fusion. In this way, ESQG can dynamically adapts each nodes awakening frequency to its dynamic network topology and importance degree of each individual sensing scope. The nodes are then turned on stochasticlly via the node awakening  probability and node importance based information fusion is conducted for tar-  get detection. Besides, an adaptive process of perception factor C is proposed to match actual situation, and automatically change according to the detected data. Experiments results demonstrate that the proposed method ESQG can reduce the number of awakening nodes to a large extent while maintaining high reliability via information fusion.

  • Reconfigurable FPGA implementation-taliem-ir

    Reconfigurable FPGA implementation of neural networks

    تومان

    This brief paper presents two implementations of feed-forward artificial neural networks in FPGAs. The implementations differ in the FPGA resources requirement and calculations speed. Both implementations exercise floating point arithmetic, apply very high accuracy activation function  realization, and enable easy alteration of the neural network’s structure without the need of a re-implementation of the entire FPGA project.

  • Secured data aggregation-taliem-ir

    Secured data aggregation in wireless sensor networks

    تومان

    Purpose – This study aims to provide a secured data aggregation with reduced energy consumption in WSN. Data aggregation is the process of reducing communication overhead in wireless sensor networks (WSNs). Presently, securing data aggregation is an important research issue in WSNs due to two facts: sensor nodes deployed in the sensitive and open environment are easily targeted by adversaries, and  the leakage of aggregateddata causes damage in the networks, and these data cannot be retrieved in a short span of time. Most of the traditional cryptographic algorithms provide security for data aggregation, but they do not reduce energy consumption. Design/methodology/approach – Nowadays, the homomorphic cryptosystem is used widely to provide security with low energy consumption, as the aggregation is performed on the ciphertext without decryption at the cluster head. In the present paper, the Paillier additive homomorphic cryptosystem and Boneh et al.’s aggregate signature method are used to encrypt and to verify aggregate data at the base station. Findings – The combination of the two algorithms reduces computation time and energy consumption when compared with the state-of-the-art techniques. Practical implications – The secured data aggregation is useful in health-related applications, military applications, etc. Originality/value – The new combination of encryption and signature methods provides confidentiality and integrity. In addition, it consumes less computation time and energy consumption than existing methods.

  • Secured data aggregation-taliem-ir

    Secured data aggregation in wireless sensor networks

    تومان

    Purpose This study aims to provide a secured data aggregation with reduced energy consumption in WSN. Data aggregation is the process of reducing communication overhead in wireless sensor networks (WSNs). Presently, securing data aggregation is an important research issue in WSNs due to two facts: sensor nodes deployed in the sensitive and open environment are easily targeted by adversaries, and the leakage of aggregated data causes damage in the networks, and these data cannot be retrieved in a short span of time. Most of   the traditional cryptographic algorithmsprovide security for data aggregation, but they do not reduce energy consumption.Design/methodology/approach Nowadays, the homomorphic cryptosystem is used widely to provide security with low energy consumption, as the aggregation is performed on the ciphertext without decryption at the cluster head. In the present paper, the Paillier additive homomorphic cryptosystem and Boneh et al.s aggregate signature method are used to encrypt and to verify aggregate data at the base station. Findings The combination of the two algorithms reduces computation time and energy consumption when compared with the state-of-the-art techniques. Practical implications The secured data aggregation is useful in health-related applications, military applications, etc. Originality/value The new combination of encryption and signature methods provides confidentiality and integrity. In addition, it consumes less computation time and energy consumption than existing methods.

     

  • The moderating impact of supply network-taliem-ir

    The moderating impact of supply network topology on the effectiveness of risk management

    تومان

    While supply chain risk management offers a rich toolset for dealing with risk at the dyadic level, less attention has been given to the effectiveness of risk management in complex supply networks. We bridge this gap by building an agent based model to explore the relationship between topological characteristics of complex supply networks and their ability to recover through inventory mitigation and contingent rerouting. We simulate upstream supply networks, where each agent represents a supplier. Suppliers’ connectivity patterns are generated through random and preferential attachment models. Each supplier manages its inventory using an anchor-andadjust ordering policy. We then randomly disrupt suppliers and observe how different topologies recover when risk management strategies are applied. Our results show that topology has a moderating effect on the ffectiveness of risk management strategies. Scale-free supply networks generate lower costs, have higher fill-rates, and need less inventory to recover when exposed to random disruptions than random networks. Random networks need significantly more inventory distributed across the network to achieve the same fill rates as scale-free networks. Inventory mitigation improves fill-rate more than contingent rerouting regardless of network topology. Contingent rerouting is not effective for scale-free networks due to the low number of alternative suppliers, particularly for short-lasting disruptions. We also find that applying inventory mitigation to the most disrupted suppliers is only effective when the network is exposed to frequent disruptions; and not cost effective otherwise. Our work contributes to the emerging field of research on the relationship between complex supply network topology and resilience.

     

  • An analytical solution-taliem-ir

    An analytical solution to the dynamic behavior of heat exchanger networks

    تومان

    A novel method combined signal flow graph of a single heat exchanger with the transfer function of streams is developed for the dynamic behaviors of heat exchanger networks problems, which are determinate factors of the process control and operation optimization in the processing industries. The transfer functions between any two nodes of heat exchanger networks including the inlet and the outlet are obtained based on the signal flow graph of the networks by block-diagram reduction, Mason’s rule and the seeking-up method. The developed method is solved by a numerical inverse Laplace transform and the analytical solution to the dynamic behavior of heat exchanger networks is presented in the time domain. The numerical results demonstrate that the presented method is more efficient and more accurate for the dynamic behaviors of heat exchanger networks problems.

  • An Anomaly Identification-taliem-ir

    An Anomaly Identification Model for Wind Turbine State Parameters

    تومان

    Identifying the anomalies of wind turbine (WT) and maintaining in time will improve the reliability of  ind turbine and the efficiency of energy use, however it is difficult toidentify the wind turbine’s  bnormal operation by the traditional threshold settings because the anomalies can be induced by multiple  actors.Therefore, this paper presents an anomaly identification model for wind turbine state  arameters,and the model can identify abnormal state which the fluctuation range of the condition parametersis within the SCADA alarm threshold. The main work is as follows: 1) in order to increase the accuracy of the prediction model, a novel BPNN model integrated genetic algorithm (GA) was employed to optimize the training method (called GABP method), data samples, and input parameter selection, respectively; 2) on this basis, the distribution characteristics of state parameter prediction errors were depicted by a T-location scale (TLS) distribution with the shift factor and elastic coefficient; 3)error abnormal index (EAI) is defined to quantify the abnormal level of the prediction error, which is used as an indicator of the wind turbine anomaly. The proposed method has been applied on areal 1.5 MW wind turbine, and the analysis shows that the proposed method is effective in wind turbine anomaly identification.

    Identifying the anomalies of wind turbine (WT) and maintaining in time will improve the reliability of  ind turbine and the efficiency of energy use, however it is difficult toidentify the wind turbine’s  bnormal operation by the traditional threshold settings because the anomalies can be induced by multiple  actors.Therefore, this paper presents an anomaly identification model for wind turbine state  arameters,and the model can identify abnormal state which the fluctuation range of the condition parametersis within the SCADA alarm threshold. The main work is as follows: 1) in order to increase the accuracy of the prediction model, a novel BPNN model integrated genetic algorithm (GA) was employed to optimize the training method (called GABP method), data samples, and input parameter selection, respectively; 2) on this basis, the distribution characteristics of state parameter prediction errors were depicted by a T-location scale (TLS) distribution with the shift factor and elastic coefficient; 3)error abnormal index (EAI) is defined to quantify the abnormal level of the prediction error, which is used as an indicator of the wind turbine anomaly. The proposed method has been applied on areal 1.5 MW wind turbine, and the analysis shows that the proposed method is effective in wind turbine anomaly identification.

  • An Overview of Mobile Ad Hoc[taliem.ir]

    An Overview of Mobile Ad Hoc Networks: Applications and Challenges

    تومان

    In the past few years, we have seen a rapid expansion in the field of mobile computing due to the  proliferation of inexpensive, widely available wireless devices. However, current devices, applications and protocols are solely focused on cellular or wireless local area networks (WLANs), not taking into account the great potential offered by mobile ad hoc networking. A mobile ad hoc network is an autonomous collection of mobile devices (laptops, smart phones ,sensors, etc.) that communicate with each other over wireless links and cooperate in a distributed manner in order to provide the necessary network functionality in the absence of a fixed infrastructure. This type of network, operating as a stand-alone network or with one or multiple points of attachment to cellular networks or the Internet, paves the way for numerous new and exciting applications. Application scenarios include, but are not limited to: emergency and rescue operations, conference or campus settings, car networks, personal networking, etc. This paper provides insight into the potential applications of ad hoc networks and discusses the technological challenges that protocol designers and network developers are faced with. These challenges include routing, service and resource discovery, Internet connectivity, billing and security.

  • Building Cisco.[taliem.ir]

    Building Cisco Multilayer Switched Networks

    تومان

    Activity Procedure: Answer these questions based on the figures. Write your answers in the appropriate spaces. Q1) In the figure, label these elements: A) Enterprise Campus B) Enterprise Edge C) Service Provider  Edge  Q2) In the figure, label these elements: A) Enterprise Campus B) Enterprise Edge C) Edge Distribution D) Service Provider Edge  Q3) In the figure, label these elements: A) core B) distribution C) access

  • Exploring antecedents-taliem-ir

    Exploring antecedents of social media usage in B2B: a systematic review

    تومان

    Purpose This paper aims to review the state-of-the-art literature on social media adoption in business- tobusiness (B2B) contexts to propose an inclusive and theoretical viewpoint to understand the antecedents of this phenomenon. Design/methodology/approach This paper presents the results of a systematic literature review. For this purpose, 29 studies published in academic journals, books and conference papers in the field of marketing and management from 2001 to 2017 were analysed. Findings The results show that the number of studies has increased in the past five years. Three different groups of antecedents are identified by considering the nature of these factors (personal, organisational and external) and analysed at two different levels of adoption: individual and firm/function. Managerial implications and future research insights are provided. Research limitations/implications This research area deserves much more attention, both theoretical and empirical, to analyse the existing classifications and develop new categories of  antecedents of social media adoption in B2B. Further studies are needed on the individual level of adoption, on new skills and capabilities required to use social media as well as on the social factors influencing usage. Practical implications The literature review allows to understand the role of personal, organisational and social antecedents and suggest ways to improve the level and quality of adoption. Originality/value Despite a considerable interest in research on social media, this paper provides the first complete framework in the new field of study concerning social media adoption in B2B.

  • Exporting firm’s engagement-taliem-ir

    Exporting firm’s engagement with trade associations: Insights from Chile

    تومان

    This study addresses the effects of the firms level of engagement with trade associations located at the  companys export market on export performance. It analyzes firm-level data from a South American  emerging economy, Chile. Results show that a stronger engagement with trade associations located at the companys export market has a positive effect on export performance. Environmental uncertainty on customer needs is confirmed as an export performance barrier, but unexpectedly, this obstacle only diminishes in a negligible factor as the level of engagement with trade associations located at the firms export market increases. This study contributes to the international management literature by investigating the direct and moderating effects of overseas trade associations on the firms export performance, and by scrutinizing on the distinctions among the cooperation determinants of local networks and networks situated at the firms export market. Practical implications are discussed.

  • ISCW SG01.[taliem.ir]

    Implementing Secure Converged Wide Area Networks

    تومان

    Implementing Secure Converged Wide Area Networks (ISCW) is an advanced course that introduces techniques and features enabling or enhancing WAN and remote access solutions. The course focuses on using one or more of the available WAN connection technologies for remote access between enterprise sites.
    This course includes cable modems and DSL with Network Address Translation (NAT), Multiprotocol Label Switching (MPLS), virtual private networks (VPNs), and network security using VPNs with IPSec encryption and Internet Key Exchange (IKE) keys. After taking this course, learners will be able to secure the network environment using existing Cisco IOS security features, and configure the three primary components of the Cisco IOS Firewall Feature set: firewall, intrusion prevention system (IPS), and authentication, authorization, and accounting (AAA). This task-oriented course teaches the knowledge and skills needed to secure Cisco IOS router networks using features and commands in Cisco IOS software, and using a router configuration application. ISCW is part of the recommended learning path for students seeking the Cisco Certified Network Professional (CCNP).

  • Implementing Secure Converged Wide Area Networks.[taliem.ir]

    Implementing Secure Converged Wide Area Networks

    تومان

    Cisco Self-Defending Network: This topic describes the Cisco Self-Defending Network strategy.  The Cisco Self-Defending Network strategy describes the Cisco vision for security systems, and helps customers more effectively manage and mitigate risks posed to their networked business systems and applications. Cisco Self-Defending Network is the Cisco response to the increasing challenge of new threats and vulnerabilities that result from constantly evolving technologies and system developments. It provides a comprehensive approach to secure enterprise networks. The Cisco Self-Defending Network strategy consists of three systems, or pillars, each with a specific purpose. By using Cisco integrated security solutions, customers can leverage their existing infrastructure to address potential threats to their network. While security risks are inherent in any network, customers can reduce their exposure and minimize these risks by deploying three categories of overlapping and complementary security solutions: „ Secure connectivity: Provides secure and scalable network connectivity, incorporating multiple types of traffic. „ Threat defense: Prevents and responds to network attacks and threats using network services. „ Trust and identity: Allows the network to intelligently protect endpoints using technologies such as authentication, authorization, and accounting (AAA), Cisco  Secure Access Control Server (ACS), Network Admission Control (NAC), identity services, and 802.1x.  The Cisco Self-Defending Network is based on a foundation of security integrated throughout the network, with constant innovations in products and technologies and crafted into systemlevel solutions. Such solutions  incorporate all aspects of the network as well as the sophisticated services needed to make it work. In addition, Cisco is working with major industry partners to ensure the completeness of the strategy.